In a display panel of this type, a drive unit is provided for each pixel electrode arranged in a matrix. Each drive unit includes a thin-film transistor element. It is ideal that all the thin-film transistor elements of the drive units operate properly. In reality, however, some of the thin-film transistor elements are faulty due to poor pressure endurance of gate insulation films, breaking of wiring lines, or the likes. When a pixel electrode is driven by a drive unit including a faulty thin-film transistor element, a dark dot or a bright dot could occur in the display panel. For this reason, Patent Literature 1 discloses a technology to prevent the faulty drive unit and the pixel electrode corresponding to the faulty drive unit from electrically connecting with each other, and the pixel electrode is electrically connected to another pixel electrode corresponding to a non-faulty drive unit.
More specifically, according to the Patent Literature 1, a plurality of pixel electrodes are arranged on a substrate in a matrix, and gate signal lines and source signal lines are formed in the row direction and the column direction respectively to connect adjacent pixel electrodes. Consequently, the pixel electrodes and the signal lines exist on the same layer, and either a gate signal line or a source signal line exists between adjacent pixel electrodes. In order to connect adjacent pixel electrodes, the signal lines are coated with an insulative film to prevent short circuit, and the adjacent pixel electrodes are connected via a metal thin film.
With the stated structure, a pixel electrode corresponding to a faulty drive unit is driven by a non-faulty drive unit electrically connected to the pixel electrode. This prevents occurrence of dark dots and bright dots on the display panel.